The present invention relates generally to the field of virtual machines, and more particularly to virtual machine migration.
In the field of computing, virtual machines (VMs), sometimes known as logical partitions (LPARs), can refer to emulated operating systems providing the functionality of a physical computer system. A hypervisor is a software or firmware component which enables the sharing and virtualization of computing resources (such as processors, persistent and volatile forms of memory, etc.) among different VMs operating on a computer system. VMs can be moved, i.e., migrated, to and from different computer systems, e.g., from a source server on which the VM operates to a destination server. A type of VM migration known as live migration refers to a process where a running VM is migrated from a source server to a destination server while still running, with minimal disruption of the operation of the VM and the services provided to end-users.
Migration of a VM from a source server to a destination server occurs via physical network adapters. In some server systems, the physical network adapters are managed by an Input/Output (I/O) virtualization component, such as, but not limited to, Virtual I/O Server (VIOS) by International Business Machines Corporation (IBM). VIOS is a component enabling the virtualization of physical I/O components, e.g., network adapters, for VMs running on a server. An I/O virtualization component (e.g., VIOS) is therefore responsible, at least in part, for the transfer of memory contents, associated with a migrating VM on a source server, to memory of a selected destination server during VM migration.